1. Field of the Invention
The present invention relates to an improved apparatus for an ultrasonic measuring of the quantity of a flow within a plastic hose by means of an emitter and a transducer which is connected to the emitter and generates a signal which is proportional to the velocity or the speed of the flow within the plastic hose and having an analyzing means which generates a signal which is proportional to the quantity of flow. The invention relates further to a method of extracting physiological liquids and adding thereto a proportional amount of a liquid coagulation preventing agent by means of an instrument system applied to a donator and a peristaltic pump for introducing the coagulation preventing agent.
2. Description of the Prior Art
The present procedure for extracting blood from donators is to lead the blood donated into a bag or a bottle, in which bag or bottle, respectively, an agent for the prevention of a coagulation as well as for conserving the blood has been previously added.
However, according to this well-known method the ideal ratio of mixture of the two components is reached not earlier than after the termination of the extraction of blood such that during the beginning of the procedure a surplus of the coagulation preventing agent is present which will destroy partly or completely important components and cells of the blood. Accordingly, the quality and durability of a blood conserve is reduced or restricted, respectively.